Investigating Emerging PFAS Destruction Technologies

By Purshotam Juriasingani, P.E., M.SAME, Rick Arnseth, Ph.D., PG, PMP, M.SAME, and Christopher Hook, P.E., M.SAME

Following recent interim guidance from the Department of Defense on how military organizations are to handle the destruction and disposal of PFAS, developing technologies that target the destruction of these forever chemicals hold possibilities for effective and efficient removal.
A resin-based filtration system in an on base groundwater treatment plant extracts and treats water before injecting it back into the ground at Shaw Air Force Base, S.C., April 13, 2023.
Interim guidance from the Defense Department has addressed potential options for disposal of PFAS-impacted waste, but destruction technologies are also being developed through small-scale and laboratory pilots. U.S. Air Force photo by Airman 1st Class Steven Cardo

In July 2023, the Assistant Secretary of Defense for Energy, Installations & Environment published two documents addressing how military organization are to handle per- and polyfluoroalkyl substances (PFAS). Together, these signal a continued commitment of the Department of Defense (DOD) to address the release of PFAS on current or former military installations and protecting the health of servicemembers, their families, and the communities around installations.

In addition to these activities to support efforts related to PFAS cleanup and treatment technologies, the department’s PFAS Task Force is also focused on identifying an effective fluorine-free firefighting alternative; establishing policies to address PFAS releases from defense sites; monitoring and communicating information about the health effects of PFAS exposure; and expanding PFAS-related public outreach.

  • The first, document released last July, Memorandum for Taking Interim Actions to Address Per- and Polyfluoroalkyl Substances Migration from DOD Installations and National Guard Facilities, encouraged base personnel to examine data from site assessments to see where they could minimize impacts of PFAS sources and begin executing interim actions.
  • The second document, Interim Guidance on Destruction or Disposal of Materials Containing Per- and Polyfluoroalkyl Substances in the United States, gave direction on treating media containing PFAS until new guidance is issued pursuant to upcoming policy expected from the Environmental Protection Agency. In particular, installations are directed to look at onsite hazardous waste storage for over 90 days or underground injection as disposal possibilities, based on site conditions.

When considering destructive technologies, installations should look at which media need to be treated, along with any specific site considerations, such as budget and proximity to civilian communities.

Because installations are beginning to utilize PFAS-free fire suppression agents, large amounts of the previous chemical concentrates and system decontamination fluids need to be disposed of or destroyed. With the volume of chemicals in consideration, DOD has described four disposal possibilities, all requiring environmental permits. These include carbon reactivation units; hazardous waste landfills; solid waste landfills that have composite liners as well as gas and leachate collection and treatment systems; and hazardous waste incinerators.

The final option for disposal was that installations could notify the Office of the Assistant Secretary of Defense for Energy, Installations & Environment of their intention to utilize additional PFAS technologies, if they were approved by the relevant state or federal agency. Ongoing developments in technologies that destroy PFAS-impacted waste mean that such applications can also provide solutions to limited disposal options.

Avoiding Waste Storage

Destructive technologies are quickly becoming the emerging solution to the limited disposal options for PFAS-impacted wastes. Researchers are investigating technologies that destroy PFAS molecules so they do not have to be stored. These methods apply high energy to break the bond between carbon and fluorine, which effectively mineralizes the chemical.

The main alternative destructive technologies are electrochemical oxidation, supercritical water oxidation, electron beam (eBeam) treatment, ball milling, and several other emerging technologies, such as plasma and ultrasound. Supercritical water oxidation, for example, is a more established technology that has been used extensively to destroy chemicals associated with munitions and is now being tested and applied for PFAS.

The main alternative destructive technologies are electrochemical oxidation, supercritical water oxidation, electron beam (eBeam) treatment, ball milling, and several other emerging technologies, such as plasma and ultrasound.

Comparing Effectiveness

Most destructive technologies are still in development. Their effectiveness and adaptability vary based on several factors. These include startup cost, operation and maintenance, use of additional chemicals/reactants, risk factors, scalability, treatment mechanism, impact of co-contaminants, and formation of by-products. Besides Energy Consumed for Total Mass Removed and Energy Consumed Per Order of Magnitude Removal, however, there are no standard methods for comparing destructive technologies that can help in selecting the best technology for field applications.

It can be complicated to track the effectiveness of PFAS destruction with the chemicals they produce as byproducts. Documenting the fate of those byproducts and their fluorine content is the key to improving destructive technologies. There are currently several research and development efforts to understand how these byproducts are produced. All of these emerging technologies have different treatment processes. A holistic approach is necessary to compare the effectiveness across media with different concentrations. Some are better for solids. Others work best on liquids or slurries. Some PFAS are easier to destroy than others, but the technologies tend to be very aggressive in terms of treatment, so utilizing high temperatures and a high electrical input can be cost-prohibitive.

Disposal Challenges

Conventional technologies widely utilized to treat PFAS are not necessarily effective for all targeted PFAS compounds. For water, conventional technologies include granular activated carbon, ion exchange resins or reverse osmosis, which consolidate and separate the chemicals from the water in order for it to be stored and ultimately disposed of as a solid or concentrated waste. However, these established concentration methods are not perfect, and there are always some chemicals that are not treated comprehensively.

Incineration quickly became the preferred solution because it destroyed the chemicals. There remain a lot of questions about what byproducts this method releases into the surrounding environment. While this method seemed viable due to its reliability for removing other types of chemicals, additional testing is required to provide confidence that it is not creating additional environmental problems.

Solid wastes contaminated with PFAS were often stored in landfills that followed federal regulations, but these facilities are also becoming reluctant to accept impacted waste until EPA releases an updated policy.

Beyond the Guidance

The treatment time for complete mineralization is also a factor. It can take as high as 70 to 80 hours to destroy PFAS in the contaminated media by these technologies, depending on the concentration of the chemicals in the media. Figuring out how to supply the high power needed can be a challenge. A large part of the research and testing is focused on lowering energy requirements to make them cost effective. Often, these types of technologies will go through the DOD Environmental Security Technology Certification Program for demonstration and acceptance. This is typically a multi-year process; some of the technologies that are developed are still going through their demonstration phase on the way to achieving acceptance. Since many of these technologies are in development, there is not a mature, price-competitive market yet. For now, the benchmark is conventional mitigation methods such as landfilling or incineration.

With so many destructive technologies being considered by funding entities, there is a lot of competition for cost effective destructive technologies. A gap frequently exists between the laboratory testing and getting the technology scaled up to something that is practical.

During this period of interim remedial guidance, any concentrating technologies may be generating waste that has to be stored, which can be a huge limitation. When considering destructive technologies, installations should look at which media needs to be treated, along with any specific site considerations, such as budget and proximity to civilian communities. Research teams are continuously brainstorming new solutions to this complex problem. Any installation with waste streams can host treatability studies or a pilot scale demonstration of these technologies.

This is a widespread issue within DOD that remains fluid as policy evolves, PFAS mitigation continues, and innovation matures. Having a toolbox of options that can be used to appropriately dispose of impacted waste is crucial. Otherwise, until solutions are found, stockpiling of waste on site will occur, which can be concerning to base personnel and civilians. With increasing urgency to develop better technologies, these tools require adequate testing and development so they can be implemented at installations across the United States and abroad.

Purshotam Juriasingani, P.E., M.SAME, is Vice President, Technology Development – Emerging Contaminants, Rick Arnseth, Ph.D., PG, PMP, M.SAME, is Senior Geochemist/Project Manager, and Christopher Hook, P.E., M.SAME, is Program Manager, Tetra Tech. They can be reached at purshotam.juriasingani@tetratech.com; rick.arnseth@
tetratech.com; and chris.hook@tetratech.com.

Collaborative Progress

While researchers can have a thorough understanding of how the technologies operate in the laboratory, field testing provides a real-world perspective. Collaboration between both groups is important for breakthrough progress in PFAS remediation.


Tetra Tech, for instance, is working with academic institutions Texas A&M University, Clarkson University, and the New Jersey Institute of Technology to research destructive technologies that can be scaled up for implementation in the field. As part of this initiative, subject matter experts identify a technology to be investigated and then make a connection with a university research group. Oftentimes, the experts meet researchers at national or international conferences to begin discussing the application of the technology they are studying. After preliminary testing in the laboratory, it is then determined whether it is worth investing more time and money to develop the technology further.

Through these research and collaboration agreements, smaller scale vessels or reactors are tested using samples from real sites. They can provide researchers with knowledge of potential issues that engineers have seen in the field so that the technology can eventually be brought to an installation to handle real world volumes of waste. Through pilot-scale testing onsite, researchers can learn about a technology’s potential success as well as inefficiencies. Then the engineers provide support to help the technology clear some of those hurdles.

Examples include the ongoing work with Texas A&M to scale eBeam technology and with Clarkson University on ball milling technology. A current project on a U.S. Air Force installation, for instance, is utilizing ultrasound technology for the destruction of PFAS. These demonstrations process samples through small-scale units, often trailer mounted, that require a small footprint and avoid mission impacts.

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